Generally, the moisturizing property of the hydrogel patch will result in hydration of the underlying skin. This can have significant consequences not only for the penetration rate of the active ingredient, but also on the occurrence of irritation [29, 30]. In this study, the patch in an area of 11.5 cm2 containing curcuminoids of about 0.24 ± 0.01 mg (approximately calculated concentration was 0.02 lg cm )2) was used. The age of volunteers averaged 43.05 ± 4.45 years. Their skin characteristics of the under-eye area (baseline value) are shown in Table IV. The obtained values showed balance in skin properties between the applied and non-applied sides